Heating apparatus.



{ N o`. 687,300. 'Patented Npv. 26, lam.

D. L. nwmNELL.

HEATNB APPARATUS.

(Applicativi med oet. 14, 169m (No Model.)

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and a resident of thecity of Montreal, Prov-A UNITED VSTATES,

PATENT OFFICE.

DAVID LANCASTER DWINNELL, OF MONTREAL, CANADA.

HEATING APPARATUS.

SPECIFICATION forming part of Letters Patent No. 687,300, dated November 26, 1901.

Application led October 14, 1897.

ince of Quebec, Dominion of Canada, have invented certain new and useful Improvements in Heating Apparatus; and I do declare that the following is a full, clear, and exact speciflcation and description of the same.

The object of my invention is to increase the efficiency of heating apparatus by the more complete combustion of the fuel consumed and applying the heat generated to the greatest advantage. -I obtain this result by means of a new system, in which the gases from the fire-box are drawn off, mixed with air, and then fed to the fire through an updraft-grate which forms one portion of the which is a downdraft-grate, and over a combustion-chamber which connects with the outlet. An air-supply around the edge of the grate feeds the fuel with the necessary quantity to produce complete combustion.

In order to illustrate my invention, I will describe the application of it to an ordinary return-fine boiler. It is equally applicable to other vstyles of boilers, furnaces, stoves, and other forms of heating apparatus.

Reference is made to the annexed drawings, in which like signs represent like parts.

Figure 1 is a sectional elevation across the grate, being on the line X X of Fig. 2. Fig. 2 is a plan view on the section-lines R R and S S, respectively, of Fig. 1. Fig. 3 is a sectional elevation on the line Z Z, Fig. l. Fig. 4 is a sectional elevation on the line Y Y of Fig. 1.

The boilerv 10 is bricked up at 2 from the grate-level upward and forms a front compartment 1a over the fire-box 1 with the walls lb 1. Beneath the grate the walls 4a 4a divide the space into three compartments, the middle one of which, 4, is closed at the end by an extension 2a of the Wall 2,' while the side compartment la connects with the lame-bed 11. A flue 3 connects the upper part of the compartment l:L with the mixing-chamber 4,an air-supplyentering thisiiue at 9. Around the grate are air-feed openings 8.

The manner in which the apparatus oper- Serial No. 655,191. (No model.)

ates is as follows :The gases arising from coal placed on the grate pass off and down the fiue 3 and, Withthe additional air which is added at 9, into the 1nixing-chamber 4. They are then drawn upthrough the grate-bars 5 and down through the incandescent fire on the bars 6, which I prefer to be water-bars, as shown in the drawings, having the divided kheader 6*?, bends 6d, inlet-feed from boiler 6b,

and outlet-return to boiler 6c. The fiame thus produced is carried under the Wall 2 to the flame-bed ll, and thence through the tubes of the boiler. The draft which draws the gases and air down through the grate l6v also draws air from the openings 8, andthe result is the complete combustion of the fuel and the combustible gases.` Only the incombustible gases are given off. Suitable dampers 8a, 9a, and 13 control the air-inlets and chimney-draft, respectively. All the air fed to the fire passes through the iire, and the combustion of the gases which it is mixed with is most complete. The smoke and gases which are drawn off by the flue 3 can be collected and used separately and air alone or gases from another source fed under the grate 5.

By means of this apparatus a great ecouomy in fuel is obtained and the highest eciency in heating and a smokeless outlet are arrived at.

The draft-circuit from fire-box to mixingi chamber is perfectly independent of and distinct from the chimney-draft.

The air-supply around the grate is arranged to be easily regulated to supply the demands of the downdraft-ire.

The ame which passes under the middle wall, in addition to the air entering through the mixingchamber, is a transparent and clear ame and carries with it a minimum of solid matter.

Having now described my invention, what I claim as new, and desire to secure by Letters Patent, is#- 1. A heating apparatus comprising a firegrate, a mixing-chamber connected with the under side of a portion of such grate, a passage connecting the space above such flre- IOO ply to such mixing-chamber for the purposes set forth.

2. A heating apparatus comprising a firegrate, a mixing-chamber connected With the under side of a portion of such grate, a passage connecting the space above such firegrate with such mixing-chamber, an air-supply connected to such passage, an opening from mixing-chamber to surface of grate, a passage down through the other portion lof said grate connecting with the outlet for the purpose set forth.

A heating apparatus comprising a firegrate a mixing-chamber connected with the under side of a portion of such grate, a passage from above grate, connecting with mixing-chamber, an air-supply to mixing-charnber, a passage down through the other portion of said grate connecting with the outlet and an air-supply on the level of the iire.

4C. A heating apparatus comprising a firegrate, a mixing-chamber connected with the under side of a portion of such grate, a passage frorn above such grate to such mixingchamber, a supply of heated air to such passage, a passage down through the other portion of such grate, connecting with the outlet for the purpose set forth.

5. A heating apparatus comprising a body portion of suitable form, a fire-grate, a mixing-chamber beneath a portion of such grate and draft-circuits from space above grate to mixing-chamber and from above grate through the grate to the chimney as set forth.

G. A heating apparatus comprising a bodyportion containing a re -grate, a mixingchamber, an air-inlet on level of such grate, a passage connecting space above grate with mixing -chamber, an air-supply thereto, a draft circuit from above grate to mixingchamber, and from above grate through grate to outlet as set forth.

7. Aheatingapparatusconsistingofagrate, mixing-chamber, a combustion-chamberleading to outlet, a Hue from above grate to mixing-chamber, an air-inlet to flue, one portion of grate over mixing-chamber adapted to an updraft, the other portion of grate over combustion-chamberadapted to a downdraft, and an air-supply from outer edges of grate.

8. Aheating apparatus consisting ofa grate, a mixing-chamber, a combustion-chamber leading to outlet, a flue from above grate, an air-inlet to mixing-chamber, one portion of grate over mixing-chamber adapted to an updraft, the other portion over combustionchamber, adapted to a downdraft, andan airsupply from edges of grate.

Signed in the presence of the two undersigned Witnesses.

DAVID LANCASTER DWINNELL.

Vtnesses:

G. A. MILLER, HANBURY A. BUDDEN. 

